Comparative Study of Simulation of Temperature Rise in Ring Main Unit

Summary

This paper addresses the temperature rise problem of the ring main unit by establishing a simplified model and conducting a comparative analysis in two temperature field-solving modules.

Abstract

The Ring Main Unit (RMU) is a critical device in power distribution systems used for connecting and distributing electricity. However, due to its compact internal structure and high current load, heat dissipation issues are particularly prominent. To address this problem, this study innovatively proposes a simplified RMU model, employing finite element simulation methods to accurately solve for the ohmic losses of conductors under actual operating conditions and obtain ohmic loss data for various components. This is the first in-depth investigation of the RMU's temperature rise problem using such a comprehensive approach. Subsequently, the temperature field was solved using two different temperature field analysis modules, with a detailed comparison and analysis of the simulation results to identify similarities, differences, and trends in temperature distribution. The results indicate that the temperature field solution model, which considers convective heat transfer, is more accurate and aligns with actual operating conditions. This research provides an innovative approach and practical solutions for the design and optimization of RMUs. Future research can further explore multiphysics coupling analysis methods to address structural design and mandatory validation issues for high and ultra-high voltage RMUs and other electrical equipment, thereby providing important insights for engineering design.

Introduction

The ring main unit is a group of high-voltage switchgear mounted in a steel metal cabinet or made of assembled spaced ring network power supply unit of electrical equipment. The overall structure of the load switch and conductive circuit consists of the conductive circuit, which includes a number of components comprising the main core of the ring unit. However, due to its compact internal structure, the ring main unit faces challenges in heat dissipation. This can lead to thermal deformation and aging when operating for extended periods in high-temperature environments. These issues not only affect the service life of the unit but also impact its insulating properties....

Protocol

1. Model

NOTE: Due to the complex structure of the ring main unit (Figure 1A), an online design software was chosen to simplify the operation of the ring main unit.

1. Modelling simplification
   1. Partially simplify the model, preserving the air box section of the RMU while removing or simplifying other components such as insulating shafts, fastening bolts, nuts, sealing components, and pressure support brackets. The simplified ve.......

Discussion

This paper is a comparative simulation analysis of the temperature rise of the ring cabinet based on engineering modeling software and finite element software, and the most suitable solution for the actual temperature rise situation is analyzed by two finite element temperature field solution modules. Thermal management is also described in Icoz²³ as a critical and essential component in maintaining the high efficiency and reliability of electronic components. The significance of conducting a comp.......

Materials

Name	Company	Catalog Number	Comments
Air	/	/	Conventional gases
Aluminum	/	/	Alloy Materials
Copper	/	/	Alloy Materials
Icepak	ANSYS company	ANSYS 2021R1	A CFD thermal simulation software
PC hosting	/	12th Generation Intel(R) Core(TM) i5-13500F CPU	Host computer equipment
SolidWorks	Subsidiary of Dassault Systemes	SolidWorks2021	An engineering software drawing tool
Steady-state thermal	ANSYS company	ANSYS 2021R1	A thermal simulation solution tool